Unsupported Browser Detected: Dear user, the browser you’re currently using is not supported by this website. Please click here for more information about the browsers we support and how to obtain them.

There is no indication of any power, the power-on indicator is not on, and the power supply fan is not running.

Check the power cord and on/off switch connector for proper installation.

Ensure that the 115/230 voltage selector switch on the back of the system is set to the correct voltage for your region. If you change the switch position, make sure to unplug the computer first. Warning: Applying 230 volts to a system set at 115 will ruin the power supply.

Make sure power is available. Make direct connections to energized wall sockets. Remove any surge protectors and power strips. Swap power cords with the monitor if possible.

Perform a power supply reset by unplugging the power cord, then press the power button in and hold for 10 seconds. Reattach the power cord and try to power on the computer.

Check the power supply diagnostic LED indications. Some newer power supplies are equipped with LEDs to indicate power supply and system board diagnostic conditions. Refer to the table below, observing the state of the Power LED on the front of the computer and the 2 diagnostic LEDs on the power supply to determine the condition.

ThinkCentre power supply LED indications

Power LED

Green
diagnostic LED

Yellow
diagnostic LED

Action

ON

ON

OFF

This is the normal condition of the LEDs when the power is OK.

OFF

OFF

OFF

Make sure the power cord is attached to a working electrical outlet.
If the electrical outlet is OK, replace the power supply.

OFF
(after the power button has been pressed)

ON

OFF

Replace the system board

ON

ON

ON

Replace the power supply

Check that the power switch is mounted to the chassis or to the fan/speaker/power switch assembly.

The switch should be securely attached to the chassis. If the switch has become dislodged, it can be pushed back into position.

Check to see if the machine boots with the cover off, using a pencil to press the power switch.

Some power switches connect directly to the system board. Make sure the wire lead from the power switch is firmly connected to the system board.

If possible, test the switch for continuity when depressed with an ohm meter.

Reseat the connector from the power supply to the system board.

Disconnect all drives and remove all adapters and memory, leaving only the processor, system board, and the power supply system board connector connected.

Reseat the system board and/or riser adapter card as applicable.

If the machine is being professionally serviced, make sure all part numbers are correct for the machine.

If you are still experiencing problems, continue to the Need more help? section.

The system shuts off unexpectedly by itself. The power indicator light is not flashing.

Ensure that the 115/230 voltage selector switch on the back of the system is set to the correct voltage for your region. If you change the switch position, make sure to unplug the computer first.Warning: Applying 230 volts to a system set at 115 will ruin the power supply.

Remove any surge protectors and power strips. Swap power cords with the monitor if possible.

Check all external cord connections for possible loose or broken connections or fasteners.

Test the machine for an extended period while booted to the System Configuration Utility. When you power on the computer, press the F1 to go to BIOS setup; you will be taken to the System Configuration Utility. If you do not experience any power issues while in the System Configuration Utility, your problem is probably being caused by software, not hardware, issues. Contact your software vendors for additional information.

Remove the system cover and verify the power supply fan and processor fan (if installed) work. The processor fan may work intermittently depending on processor temperature. The power supply fan should run continuously.

Disconnect any additional drives (such as serial or parallel hard drives, CD-ROM or DVD drives, PCI or PCI-Express adapters, or memory) that were added recently. The addition of new drive(s) or other power consuming devices could be causing the system to power off. If a new drive(s) did cause the problem, it may be defective or incompatible with the system.